Adjustable duplex electric lamp



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Many 11??? H36. MARCH/AND ADJUSTABLE DUPLEX ELECTRIC LAMP .2 Sheets-Sheet l Filed Feb. 26, 1935 IN V EN TOR;

A TTORNEY D N A H C R A M n A ADJUSTABLE DUPLEX ELECTRIC LAMP Filed Feb. 26, 1935 2 Sheets-Sheet' 2 Lll'lul A TTORNEY Patented May 26, 1936 UNITED ADJUS-IKBLE DUPLEX ELECTRIC Adolph Marcha-nd, Jackson HeightS,N Y; Application February 26, 1935,: Serial? No; 8,284

1 Claim.

The objectof the present invention is to provide an adjustable duplex electric lamp of the type particularly adapted for use on a night table or console for illumination at opposite sides of 5 the lamp base, the lamp being adapted for use between twin beds and as a reading lamp for either bed. A wide range of adjustment is provided for the lamp together with means for controlling such adjustment so that the conducting 10 wires may not be given abnormal bending or twisting which may result in short circuits through breaking of insulation, or detachment.

The invention will be described with reference to the accompanying drawings, in which:-

Fig. l is a view in elevation of an embodiment of the invention.

Fig. 2 is a fragmentary plan view of the base.

Fig. 3 is a side view of the base.

Fig. 4 is an enlarged elevation of the base, 20 partly broken away in vertical section.

Fig. 5 is an enlarged View in elevation of the upper portion of one arm and its immediately connected parts, said upper portion being shown in section.

Fig. 6 illustrates in elevation the lower end of a supporting arm, the base socket area, the arm supporting ball and the members which serve to hold the ball and the socket under spring tension.

Fig. 7 is a transverse section taken generally on the line 1-4, Fig. 5.

Fig. 8 is a plan view of the ball, socket and spring tension elements for one of the two lampholding arms, the parts being shown in position for assembly.

ferent position.

Referring to the drawings, it will be seen that the embodiment therein shown comprises a novel type of base member I having two vertical cylin- 40 drical chambers a and b rising from which is a dome Ia: closing each chamber except for a passageway of special construction later to be described.

The upper end of each chamber is rounded in conformity with a ball member 2 disposed therein. Below the ball member may be placed a washer 3 having an aperture conforming to the shape of the ball, and. the washer receives pressure of the spring 4 having its lower end abutting a plug threaded within the lower end of the chamber. The tension of the spring in each case may be adjusted by rotating the appropriate plug 5.

Each ball 2 is provided with an upwardly projecting shouldered neck 2a: threaded above the Fig. 9 shows the ball member of Fig. 8 in a dif-- shoulder. The ball, neck and spring supporting plug are centrally apertured to permit the passage of the electric conductor 6 from a suitable switch, indicated at I.

Secured upon each of the two ball necks 2a: is the threaded lower end of an arm 8, the arm in each case being longitudinally apertured, in usual practice, to permit the passage of the conductor 6.

The upper end of each arm 8 is, as shown in Fig. 5, threaded to receive an externally threaded nipple 9. Threaded upon nipple 9 is a sleeve In which at its outer end is threaded to receive a socket member I l. Within the socket member is disposed a ball l3 having a shouldered threaded neck l4 upon which lamp socket I5 is secured. The end of the arm may receive an ornamental shell l6 and upon the ball neck may be mounted a second and larger ornamental shell I! disposed rearw-ardly of a shade I8 for the lamp l9. Within sleeve Ill may be disposed a washer 2|] rearwarclly of which is a coil spring 2!. The washer will be apertured and the bearing face abutting the ball will be shaped in conformity with the latter.

By reference to Figs. 4 and 6, it will be seen that the surface of the ball 2 is formed with a channel at o shaped in the same formation as the channel c of ball I3, Fig. 8. The channel is roughly triangular and corresponds generally with the formation of aperture d in dome in: of base member I. The wall of dome aperture 11 serves to guide the appropriate ball neck 21:: carrying arm 8 from the position shown in Fig. 1 downwardly in a vertical plane and thence to the left or to the right until the neck strikes the lower right or left hand wall of the said aperture d, the wall affording a stop. The bottom wall of aperture d may have a central rise, shown in the drawings, so that the arm is better held in right or left hand position and must be given a slight upward movement prior to adjustment from right to left or vice versa. These adjustments may freely be made by partial rotation of the ball 2 appropriate to the arm moved in said adjustment, rotation of the arm, on any axial point being prevented by a stud screw 22 threaded in the dome, the stud entering channel 0* and being adapted for abutment by the continuous side wall of the channel.

A stud screw 23 similar to 22 is carried by ball socket member ll, carried at the upper end of arm 8, the stud of screw 23 entering the channel c of ball I3 and being adapted for abutment by the side wall of said channel.

When the lamp is moved downwardly on arm 8, corresponding movement of ball l3 will so position channelway c with respect to screw stud 22 that the lamp elements may be adjusted with the ball to the left or to the right in addition to the vertical adjustment. At the same time, the axial movement of the ball is limited and the wiring is protected against abnormal twisting and breaking strain.

By reason of the combined adjustment, the light may be directed to a wide range of positions without strain upon the wiring or connections notwithstanding the fact that the wiring is entirely concealed within the lamp. For example, one of the arms 8 may be adjusted to illuminate reading matter or an object whilst the second arm remains in such position as to give general illumination. Also both arms may be brought forwardly from the dotted line position shown in Fig. 4 and the lighting elements moved toward each other and given a desired adjustment for simultaneous illumination of readin matter, or an object.

Having described my invention, what I claim and desire to secure by Letters Patent, is as follows:-

In an adjustable electric lamp comprising a base member and an upwardly extending chamber formed in said base member, of a dome surmounting said chamber, said dome being formed with an aperture having a relatively wide bottom guiding wall and side walls converging above said bottom wall, a ball member in said chamber having a surface depression similar in conformation to the aperture of said dome area, a stud carried by the dome and entering the ball surface depression, and an illuminating means carried by said ball.

ADOLPH MARCHAND. 

